An insulator used in an electronic device/material field may have various reactive polarity groups on a surface to act as a charge transfer trap when forming an interface with an organic semiconductor and thus, the surface may be reformed. A scheme of processing a surface of an insulating layer used in a conventional electronic device/material field may include a self-assembly mono layer scheme, a polymer ultra thin film coating scheme, and the like. The self-assembly mono layer scheme may be applied to a semiconductor solution processing, and may provide a hydrophobic surface of an insulating layer, thereby helping enhance a performance of an organic electronic device. However, there may be a degree of difficulty in controlling a manufacturing process and environmental requirements, as well as expectations for a uniform surface characteristic over an entire area. The polymer ultra thin film coating scheme may involve a relatively simple manufacturing process. However, a solvent resistance for an organic solvent may be relatively low and thus, a subsequent solution process may not be performed. To supplement limitations of the polymer ultra thin film coating scheme, a curing agent such as bis(trichlorosilyl)hexane may be used in a macromolecular thin film coating scheme, thereby resulting in an increased surface roughness of an insulating layer.